CSCI 577B Software Engineering B
Technical Debt
Ihsan Tolga
Outline
•
•
•
•
•
•
•
Things We Have Already Experienced
What Is Technical Debt
Symptoms of Technical Debt
Technical Debt Metrics
Definition and Cost of Technical Debt From Different Perspectives
Repayment Plan
Strategies for Paying Down Technical Debt
CSSE
•
•
•
•
•
•
•
Things We Have Already Experienced
What Is Technical Debt
Symptoms of Technical Debt
Technical Debt Metrics
Definition and Cost of Technical Debt From Different Perspectives
Repayment Plan
Strategies for Paying Down Technical Debt
CSSE
Some Familiar Experience
As the process goes on, costs are rising and customer responsiveness
is falling.
Using an obscure/incomplete error message because it is too hard to
figure out how to do it right.
Rushing for a shippable product to meet to contract so getting
something done in its own way.
After a couple of years, the system is paralyzed and so it is even
cheaper to develop a new one from scratch.
CSSE
•
•
•
•
•
•
•
Things We Have Already Experienced
What Is Technical Debt
Symptoms of Technical Debt
Technical Debt Metrics
Definition and Cost of Technical Debt From Different Perspectives
Repayment Plan
Strategies for Paying Down Technical Debt
CSSE
Technical Debt
The cost associated with a lesser software system that became difficult
to maintain and improve. The debt within the system becomes a
constant anchor on software productivity and impedes the ability to
efficiently add new features. [3]
Delayed technical work that is incurred when technical short cuts are
taken, usually in pursuit of calendar-driven software schedules. Just
like financial debt, some technical debts can serve valuable business
purposes. [1]
CSSE
Technical Debt
Technical debt in two axis:
Reckless/prudent & Deliberate/Inadvertent[2]
•
•
•
•
Reckless-deliberate: “we do not have time
for design.”
Reckless-inadvertent: “What is layering?”
Prudent-deliberate: “We must ship now and
deal with consequences.”
Prudent-inadvertent: “Now we know how
we should have done it.”
CSSE
•
•
•
•
•
•
•
Things We Have Already Experienced
What Is Technical Debt
Symptoms of Technical Debt
Technical Debt Metrics
Definition and Cost of Technical Debt From Different Perspectives
Repayment Plan
Strategies for Paying Down Technical Debt
CSSE
Symptoms of Technical Debt
 Poor customer responsiveness
Management – customers
 Long delivery times
For new releases, time-to-market
 Late deliveries
Time consuming bug fixes
 Lots of defects
Major portion of development capacity goes to defect fixing
 Rising Development Costs
Higher man-hours, higher costs
 Frustrated and Poor Developer Teams
Clash between rushing for deadline – “doing it right” [1]
CSSE
•
•
•
•
•
•
•
Things We Have Already Experienced
What Is Technical Debt
Symptoms of Technical Debt
Technical Debt Metrics
Definition and Cost of Technical Debt From Different Perspectives
Repayment Plan
Strategies for Paying Down Technical Debt
CSSE
Technical Debt Metrics
• Questions to answer for eliminating existing debt & preventing future
debt[3]
•
•
•
•
How can I efficiently measure how much debt I already have?
What aspect of debt in my code are impacting me the most, or should I
be most concerned about?
How much debt is “too much”; how much is “manageable”?
How much will it cost me to get out from under my high interest debt?
• To characterize and to measure the existing debt related to project.
• Static and dynamic tools are on service. (i.e. Sonar) [4]
CSSE
Technical Debt Metrics
•
•
•
•
•
•
•
•
Duplicate code (Static)
Rules Compliance
Comments – Interfaces (Static)
Comments – General (Static)
Package Interdependencies (Static)
Method/Class Complexity (Static)
Automated Test Coverage (Dynamic)
Manual Test Coverage (Dynamic) [3]
This list of metrics also represent the priority to capture.
CSSE
•
•
•
•
•
•
•
Things We Have Already Experienced
What Is Technical Debt
Symptoms of Technical Debt
Technical Debt Metrics
Definition and Cost of Technical Debt From Different Perspectives
Repayment Plan
Strategies for Paying Down Technical Debt
CSSE
Definition and Cost Of Technical Debt From
Different Perspectives
• Customers:
•
Biggest victims in this affair. However; they usually give more credit on features
than the long-term maintainability, security and reliability. Particular customers are
in a different case.
• Help Desk:
•
Personnel in this branch suffer from almost every aspect of technical debt (poor
interface, lack of documentation, slow performance…) Even though, they do not
have direct access to solve the problem.
• Operations:
•
Especially in service-oriented business; this branch pay for the outcomes of
decision-makers. Recently emerged “DevOps” approach (Operations people and
developers work together) [2]
CSSE
Definition and Cost Of Technical Debt From
Different Perspectives
• Engineers:
•
Developers (implement the code) and maintainers (repair, modify, extend the
existing code). It is perceived as developers and strongest yet maintainers do the
hardest job.
• Marketing:
•
Customer facing people; usually must deal with the displeasure of the customers
in the cases of technical debt. Long release intervals push force them against
customers. (No need to mention about the situations in which the new release
does not work properly.)
• Management:
•
Conducting good risk management and balancing demands from different
branches & Favor a single branch/department and neglect the others which leads
taking too much technical debt or missing the advantage of taking a right amount.
[2]
CSSE
•
•
•
•
•
•
•
Things We Have Already Experienced
What Is Technical Debt
Symptoms of Technical Debt
Technical Debt Metrics
Definition and Cost of Technical Debt From Different Perspectives
Repayment Plan
Strategies for Paying Down Technical Debt
CSSE
Repayment Plan
Engagement, motivation and a plan lead exponential value to
customers.
• Engaging executive management in explaining what technical debt is.
• Explaining how it is impacting responsiveness, costs, delivery and
morale.
• Getting buy in to make the necessary investments to pay down
technical debt and proactively manage it going forward.
• Creating a realistic plan and appropriate governance model[1]
When interacting with high rank executives; it would help to explain
technical debt as analogous to financial debt.[1]
CSSE
•
•
•
•
•
•
•
Things We Have Already Experienced
What Is Technical Debt
Symptoms of Technical Debt
Technical Debt Metrics
Definition and Cost of Technical Debt From Different Perspectives
Repayment Plan
Strategies for Paying Down Technical Debt
CSSE
Strategies for Paying Down Technical Debt
After tracking technical debts in a project by using related metrics and forming a repayment
plan
• Poor coding and testing practices:
•
Often conducts from lack of time and/or knowledge to do it right. Each team
member should invest in their own knowledge and education on how to write clean
codes, related business domain and how to do their jobs optimally. [1]
• Poor system design:
•
Most architects over-focus on user features and under-focus on the actual
important qualities of a software like maintainability, performance, reuse and
adaptability which directly relate to the technical debt.[1]
• Poor Communication and Collaboration
•
Directly related to technical debt. At least a daily stand-up meetings (15 minutes at
max) for entire team to synchronize each member’s schedule. People can adjust
and collaborate on accomplishing important tasks.[1]
CSSE
Strategies for Paying Down Technical Debt
After tracking technical debts in a project by using related metrics and forming a repayment
plan
• Lack of standard development processes:
•
Companies often use a blended way of their own instead of a proven method in
which cases documentation does not reflect how it is done in practice. [1]
• Poor requirements with no common definition of done:
•
For each requirement, use case and user story there should be a common
definition of done which must be validated with management before and after
development phase. [1 ]
• Lots of manual effort for a release:
•
A few team members who are fully focused on automated tools can accomplish a
great deal of integration / testing / database setup work in a relatively short time.
• Lack of proactive investment in paying down debt:
•
Sometimes technical debt should be taken on only with a conscious decision (not
recklessly) Management side must have good deal of knowledge about technical
debt and tackling it. [1 ]
CSSE
Closing
Thank you...
Question & Answers
CSSE
References:
[1] Shriver, Ryan. “Seven Strategies for Technical Debt”. (2009).
www.projectmanagement.com (former www.gantthead.com)
[2] Allman, Eric. “Managing Technical Debt. (2012). ISSN 1542-7730. Queue –
Development Magazine Volume 10 Issue 3, March 2012 pp 10-17. New York –
USA.
[3] Eisenberg, Robert. (2012). ACM SIGSOFT Software Engineering Notes,
ISSN 0163-5948. March 2012, Volume 37, Issue 2 pp 1-6.
[4] www.sonarsource.org
CSSE